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Dieses Dokument verwendet PHP-Handbuch für chinesische Websites Freigeben
(PHP 4 >= 4.0.6, PHP 5, PHP 7)
fbsql_num_rows — Get number of rows in result
$result
)
Gets the number of rows in the given result
set.
This function is only valid for SELECT statements. To retrieve the number of rows returned from a INSERT, UPDATE or DELETE query, use fbsql_affected_rows() .
result
由 fbsql_query() 或 fbsql_db_query() 返回的结果标识符。
Returns the number of rows returned by the last SELECT statement.
Example #1 fbsql_num_rows() example
<?php
$link = fbsql_connect ( "localhost" , "username" , "password" );
fbsql_select_db ( "database" , $link );
$result = fbsql_query ( "SELECT * FROM table1;" , $link );
$num_rows = fbsql_num_rows ( $result );
echo " $num_rows Rows\n" ;
?>
[#1] daggillies at yahoo dot com [2002-04-05 12:29:27]
Note that this function will not always return the actual size of a result set. For example, if you are doing a two-table join along the lines of "SELECT * FROM T1,T2 where T1.x=T2.x" you will get a result of -1. This is due to the 'lazy execution' model in FrontBase whereby result rows are only returned as you request them. If you absolutely have to have the number of rows in advance then you will have to use COUNT(*) first. Most of the time you do not need to know the exact number of rows; it is good enough to know if the size of the result set is non-zero.
David Gillies
San Jose
Costa Rica